Temporal radiance caching

Self Cite

We present a new approach for accelerated global illumination computation in scenes with glossy surfaces. Our algorithm combines sparse illumination computation used in the radiance caching algorithm with BRDF importance sampling. To make this approach feasible, we extend the idea of lazy illumination evaluation, used in the caching approaches, from the spatial to the directional domain. Using importance sampling allows us to apply caching not only on low-gloss but also on shiny materials with high-frequency BRDFs, for which the radiance caching algorithm breaks down.

Section: Releated Workmentioning

confidence: 99%

Spatial Directional Radiance Caching

Gassenbauer

Křivánek

Bouatouch

2009

Self Cite

“…Our algorithm does not require such an extra data structure because each sampled direction in every irradiance cache record is implicitly linked to a VPL, thus dispensing additional data structures. Gautron et al [GBP07] presented a temporal (ir)radiance cache that catered for changes in the temporal domain and included computation of a temporal gradient. Their method predicted incoming lighting and how it would affect the cached samples.…”

Section: Related Workmentioning

confidence: 99%

Instant Caching for Interactive Global Illumination

Debattista

Dubla

Banterle

et al. 2009

The ability to interactively render dynamic scenes with global illumination is one of the main challenges in computer graphics. The improvement in performance of interactive ray tracing brought about by significant advances in hardware and careful exploitation of coherence has rendered the potential of interactive global illumination a reality. However, the simulation of complex light transport phenomena, such as diffuse interreflections, is still quite costly to compute in real time. In this paper we present a caching scheme, termed Instant Caching, based on a combination of irradiance caching and instant radiosity. By reutilising calculations from neighbouring computations this results in a speedup over previous instant radiosity-based approaches. Additionally, temporal coherence is exploited by identifying which computations have been invalidated due to geometric transformations and updating only those paths. The exploitation of spatial and temporal coherence allows us to achieve superior frame rates for interactive global illumination within dynamic scenes, without any precomputation or quality loss when compared to previous methods; handling of lighting and material changes are also demonstrated.

“…These methods generally have image artifacts when the scene changes; these artifacts gradually clear as new samples arrive. Temporally coherent extensions to (ir)radiance caching have been explored in [SKDM05] and more recently in [GBP07]. However, both of these approaches, despite using sparse sampling, take several minutes per frame on moderately complex scenes.…”

Section: Previous Workmentioning

confidence: 99%

Tensor Clustering for Rendering Many‐Light Animations

Hašan

Velázquez-Armendáriz

Pellacini

et al. 2008

Images from animations rendered with our algorithm, with environment illumination and multiple-bounce indirect lighting converted into 65,536 lights. By sparsely sampling the light-surface interactions and amortizing over time, we can render each frame in a few seconds, using only 300-500 GPU shadow map evaluations per frame. AbstractRendering animations of scenes with deformable objects, camera motion, and complex illumination, including indirect lighting and arbitrary shading, is a long-standing challenge. Prior work has shown that complex lighting can be accurately approximated by a large collection of point lights. In this formulation, rendering of animation sequences becomes the problem of efficiently shading many surface samples from many lights across several frames. This paper presents a tensor formulation of the animated many-light problem, where each element of the tensor expresses the contribution of one light to one pixel in one frame. We sparsely sample rows and columns of the tensor, and introduce a clustering algorithm to select a small number of representative lights to efficiently approximate the animation. Our algorithm achieves efficiency by reusing representatives across frames, while minimizing temporal flicker. We demonstrate our algorithm in a variety of scenes that include deformable objects, complex illumination and arbitrary shading and show that a surprisingly small number of representative lights is sufficient for high quality rendering. We believe out algorithm will find practical use in applications that require fast previews of complex animation.